First you have to learn to use the code tags when you post your data sample.
Learn howto use double quote to preserve spacing, see below:
Code:
# cat file
My name is David. Working on shell scripting now.
# while read LINE
do
echo $LINE
echo "$LINE"
done < file
My name is David. Working on shell scripting now.
My name is David. Working on shell scripting now.
Hi,
Is it possible to accept a filename as command line parameter and then write to that file using command redirection? i tried the below script.
outputfile=`echo $1`
echo "Writing to file" > 'echo $outputfile'
exit $returncode
but it isnt working. is there any other way to... (9 Replies)
hi
i have a file contains data
Line timeout:
START->SIGNON_REPLY,
SIGNON_REPLY->SIGNON,
Received SOT req
SOT request:
SIGNON->SOT_REPLY,
SOT_REPLY->DATA_RECEIVE,
DATA_RECEIVE->EOD,
i need to write into one line , separated by commas
please help
thanks
Satya (2 Replies)
I need to write value of variable $version at a particular line in a text file.
Line number is determined by another variable &line......I don't know how to do it in shell script ... (2 Replies)
Hi,
I have to write s script to check an input file for invalid characters. In this script I have to find the exact line of the invalid character. If the input file contain 2 invalid character sat line 10 and 17, the script will show the value 10 and 17. Any help is appreciated. (3 Replies)
Dear All,
I have a question that's been difficult to get an answer to.
I often write command line loops, e.g. find files, print name, grep for term, apply sed, etc
I use both zsh and bash.
When I write a loop e.g.
for line in `more myfile.txt`
> do
> echo $line
> done
but... (2 Replies)
Given a particular line number and a corresponding column number, can i write something in the file during run time?
For example x=1 and during runtime i want to write the value of x in column 100 of every line of a given file, then how shud that be done?
Thanks (9 Replies)
Hi,
I have 1000 files names data1.txt through data1000.txt inside a folder. I want to write a script that will take each first line from the files and write them as output into a new file. How do I go about doing that? Thanks! (2 Replies)
Hi,
I have a file whihc looks like
file_1 100 200
file_2 200 300
file_4 400 500
as the file_3 is missing so I want to replace it by
file_3 0 0
the final output would look like
file_1 100 200
file_2 200 300
file_3 0 0
file_4 400 500
Any help is highly appreciated.
Regards, (3 Replies)
Hello
I am facing a very unique problem and not able to understand why. I have written a function which will check header of the file. If header is present good else it will write the header on top
def writeHeaderOutputCSV(fileName):
# See if the file exist already
try:
... (0 Replies)
Discussion started by: radioactive9
0 Replies
LEARN ABOUT CENTOS
shell-quote
SHELL-QUOTE(1) User Contributed Perl Documentation SHELL-QUOTE(1)NAME
shell-quote - quote arguments for safe use, unmodified in a shell command
SYNOPSIS
shell-quote [switch]... arg...
DESCRIPTION
shell-quote lets you pass arbitrary strings through the shell so that they won't be changed by the shell. This lets you process commands
or files with embedded white space or shell globbing characters safely. Here are a few examples.
EXAMPLES
ssh preserving args
When running a remote command with ssh, ssh doesn't preserve the separate arguments it receives. It just joins them with spaces and
passes them to "$SHELL -c". This doesn't work as intended:
ssh host touch 'hi there' # fails
It creates 2 files, hi and there. Instead, do this:
cmd=`shell-quote touch 'hi there'`
ssh host "$cmd"
This gives you just 1 file, hi there.
process find output
It's not ordinarily possible to process an arbitrary list of files output by find with a shell script. Anything you put in $IFS to
split up the output could legitimately be in a file's name. Here's how you can do it using shell-quote:
eval set -- `find -type f -print0 | xargs -0 shell-quote --`
debug shell scripts
shell-quote is better than echo for debugging shell scripts.
debug() {
[ -z "$debug" ] || shell-quote "debug:" "$@"
}
With echo you can't tell the difference between "debug 'foo bar'" and "debug foo bar", but with shell-quote you can.
save a command for later
shell-quote can be used to build up a shell command to run later. Say you want the user to be able to give you switches for a command
you're going to run. If you don't want the switches to be re-evaluated by the shell (which is usually a good idea, else there are
things the user can't pass through), you can do something like this:
user_switches=
while [ $# != 0 ]
do
case x$1 in
x--pass-through)
[ $# -gt 1 ] || die "need an argument for $1"
user_switches="$user_switches "`shell-quote -- "$2"`
shift;;
# process other switches
esac
shift
done
# later
eval "shell-quote some-command $user_switches my args"
OPTIONS --debug
Turn debugging on.
--help
Show the usage message and die.
--version
Show the version number and exit.
AVAILABILITY
The code is licensed under the GNU GPL. Check http://www.argon.org/~roderick/ or CPAN for updated versions.
AUTHOR
Roderick Schertler <roderick@argon.org>
perl v5.16.3 2010-06-11 SHELL-QUOTE(1)